Nowadays, the water supply (and separation of salt and other chemicals) is extremely important for human consumption (drinking or general use, e.g., bathing), animal consumption, industrial use, agriculture, washing purposes, plants, trees, vegetation, and food supplies.
The drinking water is in short supply, especially for countries in the warm climate or near desert, with no or small amount of rain and snow. In addition, getting pure and drinking water from ocean or sea is very expensive and requires a lot of energy. Furthermore, the pollution for such an energy requirement is a big concern for the environment. In addition, the energy is also in short supply and expensive, e.g., for oil or coal. Furthermore, the hungry nations or people may go to war or cause riots, with suffering and disastrous results, to go after scarce resources, such as food and water. In addition, the population of the world is increasing drastically and very fast. Furthermore, the vegetation and agriculture/trees/forests are hard to maintain without the proper supply of the water. In addition, the food or water is getting more expensive and scarce for most of the world. Furthermore, the weather patterns are getting more extreme and disastrous for most of the world.
So, one needs solutions for collecting water, in an efficient and less expensive way, with less pollutions and less energy, with use of green/renewable energy, if possible, to support the plants, animals, agriculture, and human consumptions, in various applications and usages.